package com.maintainsys.util;
import org.apache.ibatis.builder.xml.XMLConfigBuilder;
import org.apache.ibatis.builder.xml.XMLMapperBuilder;
import org.apache.ibatis.executor.ErrorContext;
import org.apache.ibatis.logging.Log;
import org.apache.ibatis.logging.LogFactory;
import org.apache.ibatis.mapping.DatabaseIdProvider;
import org.apache.ibatis.mapping.Environment;
import org.apache.ibatis.plugin.Interceptor;
import org.apache.ibatis.reflection.factory.ObjectFactory;
import org.apache.ibatis.reflection.wrapper.ObjectWrapperFactory;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.apache.ibatis.transaction.TransactionFactory;
import org.apache.ibatis.type.TypeHandler;
import org.mybatis.spring.transaction.SpringManagedTransactionFactory;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.context.ApplicationEvent;
import org.springframework.context.ApplicationListener;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.event.ContextRefreshedEvent;
import org.springframework.core.NestedIOException;
import org.springframework.core.io.Resource;
import org.springframework.jdbc.datasource.TransactionAwareDataSourceProxy;

import javax.sql.DataSource;
import java.io.IOException;
import java.sql.SQLException;
import java.util.Properties;

import static org.springframework.util.Assert.notNull;
import static org.springframework.util.ObjectUtils.isEmpty;
import static org.springframework.util.StringUtils.hasLength;
import static org.springframework.util.StringUtils.tokenizeToStringArray;

/**
 *  
 * @see #setConfigLocation 
 * @see #setDataSource 
 * @version $Id$ 
 * @modify 原作者ThinkGem 2016-5-24 来自 MyBatisSpring1.2.3版本  尹晓晨修改
 */  

public class SqlSessionFactoryBean implements FactoryBean<SqlSessionFactory>, InitializingBean, ApplicationListener<ApplicationEvent> {
	  
	  private static final Log LOGGER = LogFactory.getLog(SqlSessionFactoryBean.class);
	  
	  private Resource configLocation;
	  
	  private Resource[] mapperLocations;
	  
	  private DataSource dataSource;  
	  
	  private TransactionFactory transactionFactory;
	  
	  private Properties configurationProperties;  
	  
	  private SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
	  
	  private SqlSessionFactory sqlSessionFactory;
	  
	  //EnvironmentAware requires spring 3.1  
	  private String environment = SqlSessionFactoryBean.class.getSimpleName();
	  
	  private boolean failFast;  
	  
	  private Interceptor[] plugins;
	  
	  private TypeHandler<?>[] typeHandlers;
	  
	  private String typeHandlersPackage;  
	  
	  private Class<?>[] typeAliases;  
	  
	  private String typeAliasesPackage;  
	  
	  private Class<?> typeAliasesSuperType;  
	  
	  //issue #19. No default provider.  
	  private DatabaseIdProvider databaseIdProvider;
	  
	  private ObjectFactory objectFactory;
	  
	  private ObjectWrapperFactory objectWrapperFactory;
	  
	  /** 
	   * Sets the ObjectFactory. 
	   *  
	   * @since 1.1.2 
	   * @param objectFactory 
	   */  
	  public void setObjectFactory(ObjectFactory objectFactory) {
	    this.objectFactory = objectFactory;  
	  }  
	  
	  /** 
	   * Sets the ObjectWrapperFactory. 
	   *  
	   * @since 1.1.2 
	   * @param objectWrapperFactory 
	   */  
	  public void setObjectWrapperFactory(ObjectWrapperFactory objectWrapperFactory) {
	    this.objectWrapperFactory = objectWrapperFactory;  
	  }  
	  
	  /** 
	   * Gets the DatabaseIdProvider 
	   * 
	   * @since 1.1.0 
	   * @return 
	   */  
	  public DatabaseIdProvider getDatabaseIdProvider() {
	    return databaseIdProvider;  
	  }  
	  
	  /** 
	   * Sets the DatabaseIdProvider. 
	   * As of version 1.2.2 this variable is not initialized by default.  
	   * 
	   * @since 1.1.0 
	   * @param databaseIdProvider 
	   */  
	  public void setDatabaseIdProvider(DatabaseIdProvider databaseIdProvider) {
	    this.databaseIdProvider = databaseIdProvider;  
	  }  
	  
	  /** 
	   * Mybatis plugin list. 
	   * 
	   * @since 1.0.1 
	   * 
	   * @param plugins list of plugins 
	   * 
	   */  
	  public void setPlugins(Interceptor[] plugins) {
	    this.plugins = plugins;  
	  }  
	  
	  /** 
	   * Packages to search for type aliases. 
	   * 
	   * @since 1.0.1 
	   * 
	   * @param typeAliasesPackage package to scan for domain objects 
	   * 
	   */  
	  public void setTypeAliasesPackage(String typeAliasesPackage) {  
	    this.typeAliasesPackage = typeAliasesPackage;  
	  }  
	  
	  /** 
	   * Super class which domain objects have to extend to have a type alias created. 
	   * No effect if there is no package to scan configured. 
	   * 
	   * @since 1.1.2 
	   * 
	   * @param typeAliasesSuperType super class for domain objects 
	   * 
	   */  
	  public void setTypeAliasesSuperType(Class<?> typeAliasesSuperType) {  
	    this.typeAliasesSuperType = typeAliasesSuperType;  
	  }  
	  
	  /** 
	   * Packages to search for type handlers. 
	   * 
	   * @since 1.0.1 
	   * 
	   * @param typeHandlersPackage package to scan for type handlers 
	   * 
	   */  
	  public void setTypeHandlersPackage(String typeHandlersPackage) {  
	    this.typeHandlersPackage = typeHandlersPackage;  
	  }  
	  
	  /** 
	   * Set type handlers. They must be annotated with {@code MappedTypes} and optionally with {@code MappedJdbcTypes} 
	   * 
	   * @since 1.0.1 
	   * 
	   * @param typeHandlers Type handler list 
	   */  
	  public void setTypeHandlers(TypeHandler<?>[] typeHandlers) {
	    this.typeHandlers = typeHandlers;  
	  }  
	  
	  /** 
	   * List of type aliases to register. They can be annotated with {@code Alias} 
	   * 
	   * @since 1.0.1 
	   * 
	   * @param typeAliases Type aliases list 
	   */  
	  public void setTypeAliases(Class<?>[] typeAliases) {  
	    this.typeAliases = typeAliases;  
	  }  
	  
	  /** 
	   * If true, a final check is done on Configuration to assure that all mapped 
	   * statements are fully loaded and there is no one still pending to resolve 
	   * includes. Defaults to false. 
	   * 
	   * @since 1.0.1 
	   * 
	   * @param failFast enable failFast 
	   */  
	  public void setFailFast(boolean failFast) {  
	    this.failFast = failFast;  
	  }  
	  
	  /** 
	   * Set the location of the MyBatis {@code SqlSessionFactory} config file. A typical value is 
	   * "WEB-INF/mybatis-configuration.xml". 
	   */  
	  public void setConfigLocation(Resource configLocation) {
	    this.configLocation = configLocation;  
	  }  
	  
	  /** 
	   * Set locations of MyBatis mapper files that are going to be merged into the {@code SqlSessionFactory} 
	   * configuration at runtime. 
	   * 
	   * This is an alternative to specifying "&lt;sqlmapper&gt;" entries in an MyBatis config file. 
	   * This property being based on Spring's resource abstraction also allows for specifying 
	   * resource patterns here: e.g. "classpath*:sqlmap/*-mapper.xml". 
	   */  
	  public void setMapperLocations(Resource[] mapperLocations) {
	    this.mapperLocations = mapperLocations;  
	  }  
	  
	  /** 
	   * Set optional properties to be passed into the SqlSession configuration, as alternative to a 
	   * {@code &lt;properties&gt;} tag in the configuration xml file. This will be used to 
	   * resolve placeholders in the config file. 
	   */  
	  public void setConfigurationProperties(Properties sqlSessionFactoryProperties) {  
	    this.configurationProperties = sqlSessionFactoryProperties;  
	  }  
	  
	  /** 
	   * Set the JDBC {@code DataSource} that this instance should manage transactions for. The {@code DataSource} 
	   * should match the one used by the {@code SqlSessionFactory}: for example, you could specify the same 
	   * JNDI DataSource for both. 
	   * 
	   * A transactional JDBC {@code Connection} for this {@code DataSource} will be provided to application code 
	   * accessing this {@code DataSource} directly via {@code DataSourceUtils} or {@code DataSourceTransactionManager}. 
	   * 
	   * The {@code DataSource} specified here should be the target {@code DataSource} to manage transactions for, not 
	   * a {@code TransactionAwareDataSourceProxy}. Only data access code may work with 
	   * {@code TransactionAwareDataSourceProxy}, while the transaction manager needs to work on the 
	   * underlying target {@code DataSource}. If there's nevertheless a {@code TransactionAwareDataSourceProxy} 
	   * passed in, it will be unwrapped to extract its target {@code DataSource}. 
	   * 
	   */  
	  public void setDataSource(DataSource dataSource) {  
	    if (dataSource instanceof TransactionAwareDataSourceProxy) {
	      // If we got a TransactionAwareDataSourceProxy, we need to perform  
	      // transactions for its underlying target DataSource, else data  
	      // access code won't see properly exposed transactions (i.e.  
	      // transactions for the target DataSource).  
	      this.dataSource = ((TransactionAwareDataSourceProxy) dataSource).getTargetDataSource();
	    } else {  
	      this.dataSource = dataSource;  
	    }  
	  }  
	  
	  /** 
	   * Sets the {@code SqlSessionFactoryBuilder} to use when creating the {@code SqlSessionFactory}. 
	   * 
	   * This is mainly meant for testing so that mock SqlSessionFactory classes can be injected. By 
	   * default, {@code SqlSessionFactoryBuilder} creates {@code DefaultSqlSessionFactory} instances. 
	   * 
	   */  
	  public void setSqlSessionFactoryBuilder(SqlSessionFactoryBuilder sqlSessionFactoryBuilder) {
	    this.sqlSessionFactoryBuilder = sqlSessionFactoryBuilder;  
	  }  
	  
	  /** 
	   * Set the MyBatis TransactionFactory to use. Default is {@code SpringManagedTransactionFactory} 
	   * 
	   * The default {@code SpringManagedTransactionFactory} should be appropriate for all cases: 
	   * be it Spring transaction management, EJB CMT or plain JTA. If there is no active transaction, 
	   * SqlSession operations will execute SQL statements non-transactionally. 
	   * 
	   * <b>It is strongly recommended to use the default {@code TransactionFactory}.</b> If not used, any 
	   * attempt at getting an SqlSession through Spring's MyBatis framework will throw an exception if 
	   * a transaction is active. 
	   * 
	   * @see SpringManagedTransactionFactory
	   * @param transactionFactory the MyBatis TransactionFactory 
	   */  
	  public void setTransactionFactory(TransactionFactory transactionFactory) {
	    this.transactionFactory = transactionFactory;  
	  }  
	  
	  /** 
	   * <b>NOTE:</b> This class <em>overrides</em> any {@code Environment} you have set in the MyBatis 
	   * config file. This is used only as a placeholder name. The default value is 
	   * {@code SqlSessionFactoryBean.class.getSimpleName()}. 
	   * 
	   * @param environment the environment name 
	   */  
	  public void setEnvironment(String environment) {  
	    this.environment = environment;  
	  }  
	  
	  /** 
	   * {@inheritDoc} 
	   */  
	  @Override  
	  public void afterPropertiesSet() throws Exception {  
	    notNull(dataSource, "Property 'dataSource' is required");  
	    notNull(sqlSessionFactoryBuilder, "Property 'sqlSessionFactoryBuilder' is required");  
	  
	    this.sqlSessionFactory = buildSqlSessionFactory();  
	  }  
	  
	  /** 
	   * Build a {@code SqlSessionFactory} instance. 
	   * 
	   * The default implementation uses the standard MyBatis {@code XMLConfigBuilder} API to build a 
	   * {@code SqlSessionFactory} instance based on an Reader. 
	   * 
	   * @return SqlSessionFactory 
	   * @throws IOException if loading the config file failed 
	   */  
	  protected SqlSessionFactory buildSqlSessionFactory() throws IOException {
	  
	    Configuration configuration;
	  
	    XMLConfigBuilder xmlConfigBuilder = null;
	    if (this.configLocation != null) {  
	      xmlConfigBuilder = new XMLConfigBuilder(this.configLocation.getInputStream(), null, this.configurationProperties);
	      configuration = xmlConfigBuilder.getConfiguration();  
	    } else {  
	      if (LOGGER.isDebugEnabled()) {  
	        LOGGER.debug("Property 'configLocation' not specified, using default MyBatis Configuration");  
	      }  
	      configuration = new Configuration();
	      configuration.setVariables(this.configurationProperties);  
	    }  
	  
	    if (this.objectFactory != null) {  
	      configuration.setObjectFactory(this.objectFactory);  
	    }  
	  
	    if (this.objectWrapperFactory != null) {  
	      configuration.setObjectWrapperFactory(this.objectWrapperFactory);  
	    }  
	  
	    if (hasLength(this.typeAliasesPackage)) {  
	      String[] typeAliasPackageArray = tokenizeToStringArray(this.typeAliasesPackage,  
	          ConfigurableApplicationContext.CONFIG_LOCATION_DELIMITERS);
	      for (String packageToScan : typeAliasPackageArray) {  
	        // ThinkGem 修改实体类重名的时候抛出并打印异常，否则系统会一直递归造成无法启动  
	        try {  
	            configuration.getTypeAliasRegistry().registerAliases(packageToScan,  
	                    typeAliasesSuperType == null ? Object.class : typeAliasesSuperType);  
	        } catch (Exception ex) {  
	            LOGGER.error("Scanned package: '" + packageToScan + "' for aliases", ex);  
	            throw new NestedIOException("Scanned package: '" + packageToScan + "' for aliases", ex);
	        } finally {  
	            ErrorContext.instance().reset();
	        }  
	        // ThinkGem end  
	        if (LOGGER.isDebugEnabled()) {  
	          LOGGER.debug("Scanned package: '" + packageToScan + "' for aliases");  
	        }  
	      }  
	    }  
	  
	    if (!isEmpty(this.typeAliases)) {  
	      for (Class<?> typeAlias : this.typeAliases) {  
	        configuration.getTypeAliasRegistry().registerAlias(typeAlias);  
	        if (LOGGER.isDebugEnabled()) {  
	          LOGGER.debug("Registered type alias: '" + typeAlias + "'");  
	        }  
	      }  
	    }  
	  
	    if (!isEmpty(this.plugins)) {  
	      for (Interceptor plugin : this.plugins) {
	        configuration.addInterceptor(plugin);  
	        if (LOGGER.isDebugEnabled()) {  
	          LOGGER.debug("Registered plugin: '" + plugin + "'");  
	        }  
	      }  
	    }  
	  
	    if (hasLength(this.typeHandlersPackage)) {  
	      String[] typeHandlersPackageArray = tokenizeToStringArray(this.typeHandlersPackage,  
	          ConfigurableApplicationContext.CONFIG_LOCATION_DELIMITERS);
	      for (String packageToScan : typeHandlersPackageArray) {  
	        configuration.getTypeHandlerRegistry().register(packageToScan);  
	        if (LOGGER.isDebugEnabled()) {  
	          LOGGER.debug("Scanned package: '" + packageToScan + "' for type handlers");  
	        }  
	      }  
	    }  
	  
	    if (!isEmpty(this.typeHandlers)) {  
	      for (TypeHandler<?> typeHandler : this.typeHandlers) {
	        configuration.getTypeHandlerRegistry().register(typeHandler);  
	        if (LOGGER.isDebugEnabled()) {  
	          LOGGER.debug("Registered type handler: '" + typeHandler + "'");  
	        }  
	      }  
	    }  
	  
	    if (xmlConfigBuilder != null) {  
	      try {  
	        xmlConfigBuilder.parse();  
	  
	        if (LOGGER.isDebugEnabled()) {  
	          LOGGER.debug("Parsed configuration file: '" + this.configLocation + "'");  
	        }  
	      } catch (Exception ex) {  
	        throw new NestedIOException("Failed to parse config resource: " + this.configLocation, ex);
	      } finally {  
	        ErrorContext.instance().reset();
	      }  
	    }  
	  
	    if (this.transactionFactory == null) {  
	      this.transactionFactory = new SpringManagedTransactionFactory();
	    }  
	  
	    configuration.setEnvironment(new Environment(this.environment, this.transactionFactory, this.dataSource));
	  
	    if (this.databaseIdProvider != null) {  
	      try {  
	        configuration.setDatabaseId(this.databaseIdProvider.getDatabaseId(this.dataSource));  
	      } catch (SQLException e) {  
	        throw new NestedIOException("Failed getting a databaseId", e);
	      }  
	    }  
	  
	    if (!isEmpty(this.mapperLocations)) {  
	      for (Resource mapperLocation : this.mapperLocations) {
	        if (mapperLocation == null) {  
	          continue;  
	        }  
	  
	        try {  
	          XMLMapperBuilder xmlMapperBuilder = new XMLMapperBuilder(mapperLocation.getInputStream(),
	              configuration, mapperLocation.toString(), configuration.getSqlFragments());  
	          xmlMapperBuilder.parse();  
	        } catch (Exception e) {  
	            // ThinkGem MapperXML有错误的时候抛出并打印异常，否则系统会一直递归造成无法启动  
	            LOGGER.error("Failed to parse mapping resource: '" + mapperLocation + "'", e);  
	            throw new NestedIOException("Failed to parse mapping resource: '" + mapperLocation + "'", e);
	        } finally {  
	          ErrorContext.instance().reset();
	        }  
	  
	        if (LOGGER.isDebugEnabled()) {  
	          LOGGER.debug("Parsed mapper file: '" + mapperLocation + "'");  
	        }  
	      }  
	        
	      // ThinkGem 启动刷新MapperXML定时器（有助于开发者调试）。  
	      new MapperRefresh(this.mapperLocations, configuration).run();
	        
	    } else {  
	      if (LOGGER.isDebugEnabled()) {  
	        LOGGER.debug("Property 'mapperLocations' was not specified or no matching resources found");  
	      }  
	    }  
	  
	    return this.sqlSessionFactoryBuilder.build(configuration);  
	  }  
	  
	  /** 
	   * {@inheritDoc} 
	   */  
	  @Override  
	  public SqlSessionFactory getObject() throws Exception {
	    if (this.sqlSessionFactory == null) {  
	      afterPropertiesSet();  
	    }  
	  
	    return this.sqlSessionFactory;  
	  }  
	  
	  /** 
	   * {@inheritDoc} 
	   */  
	  @Override  
	  public Class<? extends SqlSessionFactory> getObjectType() {
	    return this.sqlSessionFactory == null ? SqlSessionFactory.class : this.sqlSessionFactory.getClass();
	  }  
	  
	  /** 
	   * {@inheritDoc} 
	   */  
	  @Override  
	  public boolean isSingleton() {  
	    return true;  
	  }  
	  
	  /** 
	   * {@inheritDoc} 
	   */  
	  @Override  
	  public void onApplicationEvent(ApplicationEvent event) {
	    if (failFast && event instanceof ContextRefreshedEvent) {
	      // fail-fast -> check all statements are completed  
	      this.sqlSessionFactory.getConfiguration().getMappedStatementNames();  
	    }  
	  }  
	  
	} 